The Domain Coexistence card/section is missing from the On Demand Migration (ODM) UI screen.
Instead of the expected Domain Coexistence card, only the Hybrid card is visible.
Possible Cause 1:
The Domain Coexistence license was not purchased.
Possible Cause 2:
The account used for the purchase does not have the Billing Administrator role assigned.
Verify License Purchase
Check Billing Administrator Role
Assign Billing Administrator Role (if missing)